#include <fstream>
using namespace std;
ifstream in("pairs.in");
ofstream out("pairs.out");
long long n, x, f[1000010], ans[1000010], i, j, mx;
int main()
{
	in >> n;
	for (i = 1; i <= n; i++)
	{
		in >> x;
		f[x]++;
		mx = max(mx, x);
	}
	for (i = mx; i >= 1; i--)
	{
		for (j = i; j <= mx; j += i)
			ans[i] += f[j];
		ans[i] = (ans[i] * (ans[i] - 1)) >> 1;
		for (j = i * 2; j <= mx; j += i)
			ans[i] -= ans[j];
	}
	out << ans[1];
}